John Lott's Website

8/10/2007

The Abortion Debate Gets Heated

I guess that it would have been helpful if Ms. Marjorie Signer had actually explained why my research showing that the liberalization of abortion rules increased crime contained "many unfounded, fallacious, racist, and confused assumptions."

John Donohue also refused to comment on the actual research, but was reduced to saying this: "I am a social scientist, however, so Lott's behavior has in my mind, put him outside the bounds of scientific discourse." That will certainly settle the debate, though I can understand why Donohue is reluctant to actually discuss the facts on this issue. Since John Whitley co-authored this paper with me, does Donohue's statement tar Whitley also?

If you want to read the research, you can find it here. THe newspaper article says that I concede that abortion through its effect on "unwanted" births slightly reduces violent crime, but what I believe that I said is that it is possible. The net effect however is abortion increases violent crime.

But what is most amazing is that despite all the statistical significance being eliminated from their panel data set being eliminated when the results are done Donohue and Levitt's way with the the data they want to use, John Donohue now says what they wanted to do:

There was no warning that these were the wrong tests at all in either of their previous papers or in Levitt's book. Levitt now refers to the “collage of evidence," but the panel data was the only test that really amounted to anything worthwhile. The rest of the data was merely cross sectional or time series.

12/02/2005

Incorrect claims about the data in More Guns, Less Crime

I have received an email comparing my work to that of Steve Levitt's regarding claimed coding errors in More Guns, Less Crime. Of course, this discussion is not very accurate.

1) There are no coding errors in the data used in “More Guns, Less Crime.” The book used crime data from 1977 to 1996, and as far as I know, no academics have claimed that there were any coding errors in that data. An interesting and useful Stanford Law Review article by Plassmann and Whitley added an additional four years to the data and the problem arose in this additional data. Overall, less than 200 cells out of 7.5 million cells were accidentally left blank. More important, the results that Plassmann and Whitley noted were the results which they thought were the correct ones were not affected at all by this minor change in the data.

My own work concentrated on murder rates, but I also included fixed effects. Donohue and Levitt never provided us with all their data or their regressions and would never answer any questions that we had so I just assumed that they had included fixed effects from the beginning. It would have been nice if they had provided us with this same information years ago.

On the substance of Donohue's work on guns, I would direct people to this paper by Plassmann and Whitley. There are two straightforward points that they make. 1) That the graphs at the beginning of the Ayres and Donohue work are very misleading because they don't make it clear that the sample of states is changing. The crime rates clear fall for a decade and a half and the sudden increase isn't real for the remaining states. It just looks like an increase because the couple of rural states that remain did not experience the decline in murder rates that more urban states experienced after right-to-carry laws were passed. 2) The second claim has to do with them fitting an intercept and line to the data and then limiting their reported impact on crime to only five years. Often there is no problem with this, but as Plassmann and Whitley clearly show it doesn't fit in this case. The Ayres and Donohue approach implies that crime initially increase (despite the fact that the year by year data discussed in point (1) doesn't, and it is just an artifact of their estimates over predicting in the early years because they are fitting this straight line with an intercept shift to crime that is falling at an increasing rate. But to compound the problem, they only discuss what the estimates mean for the first five years. Even with this approach if they had picked the sixth year it would have reversed their claims.

I also think that it is pretty clear why they find it difficult to debate either guns or abortion. Steve Landsburg was very nice to suggest in April that Levitt and I have a discussion at Rochester this fall, but I haven't heard anything back. I immediately wrote back saying that I was interested. Landsburg wrote in April that:

"Our department would like to arrange, sometime in the fall, to have you and Levitt visit simultaneously and give back-to-back workshops on guns, abortion or both. We want to hear your criticisms of each others' work and your responses to those criticisms. We *don't* want this to turn into a debate; we want it to be an academic seminar with all the usual rules of logic and evidence. The presenter is presumed to have the floor; there is an expectation of periodic interruptions from the audience; but there's also someone in charge to cut off questioning if it starts to take over the seminar. We would most assuredly *not* advertise this event to the general public, because we don't want an audience of advocates for any point of view. Ideally, we'd have you both here for two days, with you presenting on one day and Levitt presenting on the other. We are open to alternative suggestions. We'd pay you both an honorarium of some size to be determined, though surely far less than you deserve. We'll do what we can to make it attractive, though."

I am posting this because of an email that I received asking questions about Donohue's cancelation last fall.

5/07/2005

Abortion and Crime "debate" at the University of Chicago Scheduled for May 25th

The University of Chicago Federalist Society has tried for a third time to set up a debate between myself and John Donohue. Since the last two debates on the issue of guns at the University of Chicago were canceled at the last moment with Donohue withdrawing from one debate with just 2 days to go, I thought that we might have more luck scheduling a debate on another topic that is getting a lot of attention these days: abortion and crime. Donohue and Steve Levitt were the coauthors on a paper that got a lot of attention on this issue and Levitt as also recently coauthored a book with Steve Dubner that again goes over the issue. All three were asked to pick a time to debate the issue, but even though Donohue is free on the 25th and despite all the attention currently being given to the abortion research, none of them were willing to debate their work on abortion with me. (I think that I know why.) I will still be presenting on the 25th with the hope that Donohue will change his mind and defend his research.

I know that you are not going to be happy about this, but unfortunately, Professor Donohue cannot make it on the 13th of April. I am currently trying to work out the 21st (a Thursday with him). This time it really is more my fault. If you think that you could make it on the 21st (if that works out--I will let you know when Professor Donohue has his plane reservations in his hands), then we, of course, will pay for your current ticket and/or any changes that you have to make (or for both your current ticket and a new one if it is unalterable). If, on the other hand, you don't think you might be able to make it on that date or any other later in the quarter, I completely understand (obviously, we will still take care of your current reservation).

You have been the most patient and flexible speaker I could imagine and I feel as though you have been treated rather shabbily. I am really sorry about that. I still really hope that this event works out, if it does, I really feel like it might the best of our entire year. However, if it does not, I have nevertheless enjoyed working with you and I still really appreciate everything that you did for us in the fall at the last minute as well. Thank you very much, and I regret that I, once again, must convey my apologies.

Joe

Notes from me: Bold markings added. Before I bought my plane ticket, I had asked Joe in an email well before this one whether everything had been set up and he confirmed that they had. Unlike the first event being cancelled by Donohue with just two days to go, I have my suspicions about what happened here and I suspect that Joe is falling on his sword to provide cover. I was so mad that Donohue would cancel the first event the way he did, I have my suspicions that Joe is trying to keep things undercontrol by taking the blame "this time."

11/30/2004

Donohue withdraws from Thursday's University of Chicago debate on Guns

Disappointingly, John Donohue has at the last minute withdrawn from our scheduled debate on Thursday (see note for 11/29 below). I will still give a talk, though I will instead discuss the changing judicial confirmation process. Here was the advertising of the debate in the Chicago Daily Law Bulletin:

Chicago Daily Law Bulletin

November 26, 2004, Friday

SECTION: Pg. 3

LENGTH: 921 words

HEADLINE: A Web of plans at Illinois schools

BYLINE: JERRY CRIMMINS

. . .

University of Chicago Law School

- At 12:15 p.m. Thursday, Dec. 2, at the law school, the Federalist Society will present a debate entitled, "Do More Guns Result in Less Crime?" John Lott, resident scholar at the American Enterprise Institute for Public Policy Research and author of " More Guns, Less Crime: Understanding Crime and Gun Control Laws," will debate Yale Law School Professor John Donohue, author of "Shooting Down the ' More Guns, Less Crime' Hypothesis."

UPDATE: When I gave my talk at Chicago, I asked the students if they knew what had happened, but no one apparently understood why Donohue really backed out of the debate just a couple of days before the event. The debate had been set up months in advance. I had received the same emails that Donohue and Bernard Harcourt, the moderator, received confirming the event more than a month in advance. The emails were cc'd to my address, Donohue's, and Harcourt's at the same time. If there had been some misunderstanding, Donohue should have notified everyone much earlier than two days before the event.

UPDATE 2: Here are some of my very early email correspondance with Joe Cascio, with the University of Chicago Federalist Society, from the just the first half of September. The claim has been made that the event wasn't confirmed until November 29th, but I have it first confirmed in September and then several emails after that checking on the event (including just asking if people had any questions, confirming flights, and setting up the ground rules for the debate).

Great. The topic is "Do more guns (i.e. less restrictive gun laws) mean less crime?" As far as format, anything mutually agreeable to you and Professor Donohue would be fine, but we had in mind a debate with fifteen minutes for you to speak, then fifteen minutes for Professor Donohue, then ten minutes for you, then ten minutes for him, followed by ten minutes of student questions. Please let me know if that's acceptable to you. In any case, thank you very much for accepting our invitation and I'm really looking forward to this event. Please let me know if you will need a hotel room the night of the first.

Joe

Quoting John Lott :

That should be fine. What exactly is the topic? What are the ground rules?

On Sep 9, 2004, at 6:40 PM, jcascio@uchicago.edu wrote:

Dear Dr. Lott,

I'm sorry I didn't respond sooner to your message. I was out of town for a bit, then I checked with Donohue and Harcourt to see what day that you had said you would be available would work for them. How about December 2? We could have the debate at lunch and if you need to stay the night before we could put you up at the Omni downtown. In any case, please let me know if this can work out and thanks for your patience.

About Me

Name: John Lott

Location: Virginia, United States

Amazed how lucky I am that I have had jobs where I could just think about whatever I wanted to think about.
This summer I will be moving to the University of Maryland. Previously I held positions at the University of Chicago, Yale University, Stanford, UCLA, Wharton, and Rice and was the chief economist at the United States Sentencing Commission during 1988 and 1989. I have published over 90 articles in academic journals. I received my Ph.D. in economics from UCLA in 1984.